This invention provides an apparatus for packaging flexible mineral fiber materials into a compressed package. Specifically, this invention pertains to an apparatus for use in packaging glass fiber insulation material into a tight compressed rolled package.
The manufacture of glass fiber insulation materials usually includes a final manufacturing process step in which the product is carried on a conveyor belt or its equivalent and is compressed to a fraction of its former volume. The compressed insulation product is delivered to a packaging machine which rolls the insulation material into a compressed roll-up or packages the insulation material in compressed batts. The compression of the glass fiber insulation material must be performed in such a manner that the integrity of the product is not diminished. If the material is overcompressed, the glass fiber will crush and the insulation value will be diminished. If the material is compressed, allowed to recover and compressed again during the roll-up step, the glass fiber integrity is weakened and the product is degraded. Therefore, it is important to gradually compress the insulation material immediately prior to the final packaging step. This objective has been addressed by U.S. Pat. No. 4,602,471 which discloses and claims the use of a compression chute positioned in an upstream position during the initiation of the roll-up of the pack.
New problems with maintaining the integrity of the insulation pack arose with the incorporation of compression chutes, such as the '471 invention into the packaging process. Rapid compression of the insulation pack within the compression chute created a large amount of compressed air. This resulted from the insulation material traveling through the compression chute at a rate exceeding the rate which the air can escape during the compression process. The tendency to increase manufacturing line speeds and the present-day capability of manufacturing wider and thicker insulation packs presented a new challenge to provide for the efficient escape of such compressed air as the insulation pack is processed through the compression chute. If the insulation pack travels through the compression chute at a rate sufficient to deny the escape of compressed air, the pack may explode or burst out backwards from the entrance of the compression area or the air may escape through the sides of the pack thereby damaging the pack integrity, pack edges and distorting the pack shape. U.S. Pat. No. 4,653,397 has addressed this problem by providing a top surface of a compression chute having apertures located throughout which provide for venting of the compressed air during the act of compressing the insulation pack.
However, it is still desirable to provide an apparatus which compresses the glass fiber of the insulation material straight down into the insulation pack. These prior compression chutes sometimes pull on the insulation material to shift the top of the pack backward as the pack is compressed thereby creating a tendency in the insulation material to pull and shift during compression. This phenomena obviously damages the overall integrity and insulation value of the end product. Another problem, during compression, which has yet to be addressed is the tendency of the glass fiber material to shift in a direction transverse to the machine direction, thus creating an uneven buildup of insulation material on one side of the pack. This is known as the parallelogram effect. Finally there is a demand for an apparatus which guides the compressed glass fibrous material into a desired orientation upon entering the packaging machine, such as a roll-up apparatus. If the material is not "squared" to the packaging machine the material will roll in an uneven manner creating an undesirable spiral buildup on the edge of the roll-up. This is commonly known as telescoping.
It is an object of this invention to provide an improved compression chute which allows compressed air to evenly escape from the pack during compression without damaging the integrity of the glass fiber.
It is another object of the invention to provide a compression chute which compresses the insulation pack straight down and discourages the glass fiber material from shifting during compression.
Yet another object of the present invention is to provide a compression chute which guides the insulation material into the packaging apparatus in a desired orientation to discourage telescoping of the insulation material during roll-up.